/*
 * Copyright 2016 The Cartographer Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef CARTOGRAPHER_MAPPING_SUBMAPS_H_
#define CARTOGRAPHER_MAPPING_SUBMAPS_H_

#include <memory>
#include <vector>

#include "Eigen/Geometry"
#include "cartographer/common/math.h"
#include "cartographer/common/port.h"
#include "cartographer/mapping/id.h"
#include "cartographer/mapping/probability_values.h"
#include "cartographer/mapping/proto/serialization.pb.h"
#include "cartographer/mapping/proto/submap_visualization.pb.h"
#include "cartographer/mapping/trajectory_node.h"
#include "glog/logging.h"

namespace cartographer
{
    namespace mapping
    {

        // Converts the given probability to log odds.
        inline float Logit(float probability)
        {
            return std::log(probability / (1.f - probability));
        }

        const float kMaxLogOdds = Logit(kMaxProbability);
        const float kMinLogOdds = Logit(kMinProbability);

        // Converts a probability to a log odds integer. 0 means unknown, [kMinLogOdds,
        // kMaxLogOdds] is mapped to [1, 255].
        inline uint8 ProbabilityToLogOddsInteger(const float probability)
        {
            const int value = common::RoundToInt((Logit(probability) - kMinLogOdds) * 254.f / (kMaxLogOdds - kMinLogOdds)) + 1;
            CHECK_LE(1, value);
            CHECK_GE(255, value);
            return value;
        }

        // An individual submap, which has a 'local_pose' in the local map frame, keeps
        // track of how many range data were inserted into it, and sets
        // 'insertion_finished' when the map no longer changes and is ready for loop
        // closing.
        class Submap
        {
        public:
            Submap(const transform::Rigid3d &local_submap_pose) : local_pose_(local_submap_pose)
            {
            }

            virtual ~Submap()
            {
            }

            virtual proto::Submap ToProto(bool include_grid_data) const = 0;

            virtual void UpdateFromProto(const proto::Submap &proto) = 0;

            // Fills data into the 'response'.
            virtual void ToResponseProto(const transform::Rigid3d &global_submap_pose, proto::SubmapQuery::Response *response) const = 0;

            // Pose of this submap in the local map frame.
            transform::Rigid3d local_pose() const
            {
                return local_pose_;
            }

            // Number of RangeData inserted.
            int num_range_data() const
            {
                return num_range_data_;
            }

            void set_num_range_data(const int num_range_data)
            {
                num_range_data_ = num_range_data;
            }

            bool insertion_finished() const
            {
                return insertion_finished_;
            }

            void set_insertion_finished(bool insertion_finished)
            {
                insertion_finished_ = insertion_finished;
            }

            int indexLocal_ = 0;

        private:
            const transform::Rigid3d local_pose_;
            int num_range_data_ = 0;
            bool insertion_finished_ = false;
        };

    } // namespace mapping
} // namespace cartographer

#endif // CARTOGRAPHER_MAPPING_SUBMAPS_H_
